Machine for forming brake drums



March 15, 1932.

R. W. GLASNER ET AL MACHINE FOR FORMING BRAKE DRUMS Filed May 10 1950 4 Sheets-Sheet. l

March R. w. GLASNER ET AL 1,849,670

MACHINE FOR FORMING BRAKE DRUMS Filed May 10, 1950 4 Sheets-Sheet 2 TH 15, 1932. I R w GLASNER ET AL 1 849,670

MACHINE FOR FORMING BRAKE DRUMS Filed May 10, 1930 4 Sheets-Sheet 5 nlmh. fi Ja I M 16M I r II. M 1 i I! l l I L] l g :22 I. 12% QQ 66 [Hl H 6%? I I l 132, I I 'i l I 3 6Q i as 1 y ZZ March 15, 1932. R, w. GLASNER ET AL 1,349,670

MACHINE FOR FORMING BRAKE DRUMS Filed May 10, 1930 4 Sheets-Sheet 4 ZQQ.

Patented Mar. 15, 1932 UNITED STATES PATENT OFFICE RUDOLPH W. GLASNER- AND FREDRICH J'. RODE, OF CHICAGO, ILLINOIS MACHINE FOR FORMING BRAKE DRUMS Application filed May 10,

This invention relates to improvements in machines for forming brake drums from sheet metal by a drawing operation and which drums are particularly adapted, though not necessarily limited in use with wire wheels, and one of the objects of the invention is to provide improved means whereby a. complete brake drum will be formed during one cycle of operation of a double action press and which drums have heretofore necessitated two or more operations in the production thereof.

A further object is to provide an improved machine of this character for forming a brake drum having a circumferentially disposed brake flange.

To the attainment of these ends and the accomplishment of other new and useful objects as will appear, the invention consists in the features of novelty in substantially the construction, combination and arrangement of the several parts, hereinafter more fully described and claimed and shown in the accompanying drawings illustrating this invention, and in which Figure 1 is a view in elevation of a double action press of this character constructed in accordance with the principles of this invention.

Figure 2 is an enlarged detail sectional view of a portion of the magine showing the forming dies in one position.

Figure 3 is a view similar to Figure 2, showing the forming dies in what might be termed the second position.

Figure 4 is a view similar to Figure 2, showing the dies in what might be termed the final position during the forming operation.

Referring more particularly to the drawings the numeral designates the bed of the machine having uprights 11 provided with a ram 12 slidable upon the uprights. The ram is connected by means of links 13 to a crank shaft 14.

Concentrically arranged with the ram is a plunger 15 which is connected by means of a link 16 with another crank shaft 17 and the crank shafts receive their motion from any suitable source of power.

Arranged to operate below the bed of the 1930. Serial No. 451,260.

press is a pressure pad 18 which is connected with a piston rod 19, the latter in turn being connected with pistons (not shown) operating in cylinders 20, the cylinders and pistons constituting cushioning devices for yieldingly resisting the movement of the pressure pad 18 in one direction.

All of the above referred to parts are of the ordinary and well known construction.

Mounted upon the bed 10 of the machine is a bed plate 2l and mounted upon the bed plate in any suitable manner is a support 22 upon which a die 23 is secured.

Encompassing the die 23 is a work holder 24, the latter being supported by means of pins 25 that pass loosely through the bed plate 21 and engage and rest upon the pressure pad 18 so that when the cylinders are supplied with fluid under a predetermined pressure, and the work holder 24 is lowered, the pressure pad-18 will be lowered and the movement of the pressure pad and the work holder will be yieldingly resisted by the fluid pressure in the cylinders 20.

Mounted upon the support 22 is an annular member 25 which projects over an opening 26 in the support 22 in which the work holder 24 operates and the work holder is provided with a shoulder 27 adapted to engage the portion of the member 25 which projects over the recess 26 in the support 22 to limit the movement of the work holder 24 in one direction.

An annular member 28 is provided for securing the member 25 in position through the medium of fastening bolts 29.

Flexibly connected to the ram 12 through the medium of a connecting member 30 is a die 31, and in order to provide the flexible connection any suitable means may be provided such as fastening bolts 32 which pass loosely through a portion of the member 30. Nuts or collars 33 are provided on the end of the bolts 32 and springs 34 are interposed between the collars 33 and the member 30, one end of the springs engaging each. The springs tend normally to hold the member 30 against the end of the ram 12, but will yield under abnormal working conditions to permit of the accurate shaping of the corners of the work.

The die 31 co-operates with the die 23 and encompassing the die 31 is another work holder 35 which is provided with a portion 36 forming a cutting edge that co-operates with the edge of the member 25 for shearing the material. This member 35 is provided with a shoulder 37 which overhangs a portion of the die 31 and thereby serves as a means for limiting the movement of the work holder 35 in one direction.

Pins 38 pass loosely through the member and rest upon the work holder 35. These pins are engaged by a head 39 on the plunger 16 and serve as a means for lowering the work holder with respect to the die 31 and so that the work holder 35 will co-operate with the work holder 24.

The die 23 is provided with an opening 40 therethrough arranged in alinement with the opening 41 in the support 22 and with an opening 42 in the bed plate 21, so that punchings 43 of the material will be dischargedtherethrough.

Carried by the head 39 is a punch 44 which passes through a suitable opening 45 in the die 31 and also is adapted to enter the opening 40 in the die 23.

The normal position of the parts are as shown in Figure 2, at which time the top of the work holder 24 will be flush with the top of the die 23 so that the work 46 may rest thereupon.

The work holder 35 will then be lowered with respect to the die 31 so as to be supported by the shoulder 37 engaging the edge of the die 31 and the springs 34 will hold the member 30 against the lower edge of the ram 12.

When the ram and plunger are lowered from the position shown in Figure 2, the work holder 35 will co-operate with the work holder 24 to clamp the work and will hold the work, and the work holder 24 will he held against lowering movement by the pressure cushion 20, and the plunger 16 will then lower the die 13 with respect to the work holder 35.

The die 31 co-operating with the die 23 will shape the work over the latter as shown in Figure 3, before the work holder 35 is lowered sufficiently to depress the work holder 24. The pressure in the cushion 20 will during this portion of the operation hold the work holder 24 and consequently the work holder 35 against lowering movement while the die 31 is shaping and completing the shaping of the work over the die 23. At the completion of this shaping of the central portion of the work the plunger 16 will operate to force the work holder 35 downwardly and with it the work holder 24 from the position shown in Figure 3 to the position shown in Figure 4, causing the peripheral portion 47 of the work to be cut off as shown in Figure 4, and upon a still further movement of the work holders 35 and 24 in the same direction, the outer or peripheral portion of the work will be shaped over the peripheral edge of the die 23, as shown in Figure 4. At the completion of the shaping of the central portion of the Work over the die 23, the periphery of the work will rest upon the cutting die 25.

As the ram and plunger rccede from the work the co-operating dies and the work holder 24 will be returned to normal position by thepres ure of the fluid in the cushion.

As a means for holding the work holder 24 and the pressure pad 18 against return movement immediately with the ram and plunger, means may be provided for arresting this movement such as by means of a locking device, the specific construction and operation of which forms no part of the present invention but is fully described in applications Serial Numbers 365,961 and 365,962, filed May 25, 1929, and is referred to herein for the purpose of giving a clear understanding of the invention.

Suiiice it to say that the fluid for the cushion is supplied from a suitable source through a pipe 48, one branch 49 of which leads to a valve casing 50. A pipe 51 leads from the valve casing and is directed through a branch pipe 52 to the upper sides of the pistons in the cylinders 20.

A rotary element 53 provided with cams 54 is provided for operating the valves in the casing to control the flow of the fluid to one side or the other of the pistons.

The element 53 is operated in any suitable manner such as by means of an endless flexible member 55 passing over a sprocket 56 connected to the element 53 and also over a sprocket 57 which is connected with a gear 58 which in turn meshes with a gear 59. The gear 59 is rotated by means of a flexible element 60 from any suitable movable part of the press such as one of the crank shafts.

After the central portion of the drum has been formed and during the formation of the outer or peripheral portion thereof to produce the brake flange, the punch 44 will penetrate the drum to form the desired opening at the center thereof, the punching 43 being discharged through the registering openings 4041 and 42.

It will therefore be manifest that the strains or high pressures that are necessary to do the punching and blanking operations will be relieved from the blank or work holders, and that all of the punching and trimming are done after the blank holder has come to rest, the punching and shearing being done by the punch of the press.

.Vhile the preferred form of the invention has been herein shown and described, it is to be understood that various changes may be made in the details of construction and in the combination and arrangement of the several parts, within the scope of the claims, without departing from the spirit of this invention.

What is claimed as new is 1. In a double acting press for forming,

I the last said reciprocable member and movable with and with respect to the last said die, the last said work holder being responslve in its operation to the actuation of the other of said reciprocable members, and a cutting edge connected with the last said work holder and co-operating with said cutting die, the trimming operation of the blank being performed after the said shaping dies have come to rest after the completion. of their shaping operation.

2. In a double action press for forming substantially cup shaped articles, a stationary die, a reciprocable die co-operating therewith for shaping the central portion of the blank and thereafter operating as a blank holder, co-operating work holders associated with the shaping and clamping dies for holding the work while being shaped by said dies, said work holders being movable with relation to their respective dies, means for yieldingly resisting the movement of one of said work holders in one direction, and means for trimming said' blank after the said blank holder has come to rest in the cycle of operation of the press, whereby the work holder will be relieved of the strains or high pressures that are necessary to perform the trimming or blanking operations.

3. In a double action press for forming substantially cup shaped articles, a stationary die, a reciprocable die co-operati'ng therewith for shaping the central portion of the blank and thereafter operating as a blank holder, co-operating work holders associated with the shaping and clamping dies for holding the work while being shaped by said dies, said work holders being movable with relation to their respective dies, means for yieldingly resisting the movement of one of said work holders In one direction, and means for trimming and for punching said blank after the said blank holder has come to rest in the cycle of operation of the press, whereby the work holder will be'relieved of the strains or high pressures that are necessary to perform the trimming and punching operations.

4. In a double action press for forming substantially cup shaped articles, a stationary die, a reciprocable die co-ope'rating therewith to form the central part of the blank, said dies thereafter constituting blankholders, work holders associated with and movable with respect to each of the dies for holding the work while being shaped by said dies, means for yieldingly holding the work holders against movement in onedirection with respect to their associated dies and against the stress of which last recited means the work holders are movable whenthe said reciprocable die comes to rest, and means responsive to the last said movement of said work holder for blanking or trimming the blank.

5. In a double action press for forming substantially cup shaped articles, a stationary die, a reciprocable die co-operating therewith to form the central part of the blank, said dies thereafter constituting blank holders, work holders associated with and movable with respect to each of the dies for holding the work while being shaped by said dies, means for yieldingly holding the work holders against movement in one direction with respect to their associated dies and against the stress of which last recitedmeans the work holders are movable when the said reciprocable die comes to rest, and means operating after the said movable die has come to rest for punching and trimming or blanking the work, whereby the said work holder will be relieved of all stresses and strains necessary to such punching and. trimming operation.

In testimony whereof we have signed our names to this specification, on this 12th day of April, A. D. 1930.

RUDOLPH W. GLASNER. FBEDRICH J. RODE. 

